\documentclass[12pt]{article}
\usepackage{amsmath,amssymb,amsfonts}
\begin{document}
Let $X$ be a reflexive Banach space and $(x_n)_{n\geq 0}$ a nonexpansive
(resp., firmly nonexpansive) sequence in $X$.
It is shown that the set of weak $\omega$-limit points of the
sequence $(x_n/n)_{n\geq 1}$ (resp., $(x_{n+1}-x_n)_{n\geq 0})$ always
lies on a {\it convex} subset of a sphere centered at the origin of radius
$d=\lim_ {n\rightarrow \infty}\| x_n/n\|$. This fact quickly yields
previous results of B. Djafari Rouhani as well as recent results of
J.S. Jung and J.S. Park. Potential applications are also discussed.
\end{document}